HP 39gs_40gs_Mastering The Graphing Calculator_English_E_F2224-90010

Changing Font

Although the default font is very easy to read, it is quite large and often

makes parts of the expression or result extend off the screen. Changing

to a small font can help with this, at the cost of making the characters a

little more difficult to read. The

Change Font command is found on the

menu. It is a toggle command – it changes to small font if in

large mode and vice versa.

Contrasting screens are shown to the right:

Erasing, copying, cutting and pasting

When you press the

DEL button in the CAS editor the effect is basically

to remove nodes of the tree. The first node deleted is the one furthest

right in the currently highlighted section.

For example, if the highlight was as shown in the

screen above, then the current focus would be on

node B in the tree shown right. Successively pressing

DEL would begin at node E, deleting first the node’s

contents then the operation (multiply) which connected

it to the tree. Try it and see.

This process is best seen with experimentation. My

experience has been that if you are simply wishing to

edit a small portion of the expression then the best

method may be to use the ‘Edit Expr.’ command in the

menu. The tree structure used by the editor

means that although it is usually very easy to add new

operations and expressions within an existing one, it

can sometimes be frustratingly difficult.

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